2 * Sony OpenMG (OMA) demuxer
4 * Copyright (c) 2008 Maxim Poliakovski
5 * 2008 Benjamin Larsson
8 * This file is part of Libav.
10 * Libav is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
15 * Libav is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with Libav; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 * This is a demuxer for Sony OpenMG Music files
29 * Known file extensions: ".oma", "aa3"
30 * The format of such files consists of three parts:
31 * - "ea3" header carrying overall info and metadata. Except for starting with
32 * "ea" instead of "ID", it's an ID3v2 header.
33 * - "EA3" header is a Sony-specific header containing information about
34 * the OpenMG file: codec type (usually ATRAC, can also be MP3 or WMA),
35 * codec specific info (packet size, sample rate, channels and so on)
36 * and DRM related info (file encryption, content id).
37 * - Sound data organized in packets follow the EA3 header
38 * (can be encrypted using the Sony DRM!).
40 * CODEC SUPPORT: Only ATRAC3 codec is currently supported!
45 #include "libavutil/intreadwrite.h"
46 #include "libavutil/des.h"
51 #define EA3_HEADER_SIZE 96
52 #define ID3v2_EA3_MAGIC "ea3"
53 #define OMA_ENC_HEADER_SIZE 16
56 OMA_CODECID_ATRAC3 = 0,
57 OMA_CODECID_ATRAC3P = 1,
63 static const AVCodecTag codec_oma_tags[] = {
64 { CODEC_ID_ATRAC3, OMA_CODECID_ATRAC3 },
65 { CODEC_ID_ATRAC3P, OMA_CODECID_ATRAC3P },
66 { CODEC_ID_MP3, OMA_CODECID_MP3 },
69 static const uint64_t leaf_table[] = {
70 0xd79e8283acea4620, 0x7a9762f445afd0d8,
71 0x354d60a60b8c79f1, 0x584e1cde00b07aee,
72 0x1573cd93da7df623, 0x47f98d79620dd535
75 typedef struct OMAContext {
76 uint64_t content_start;
93 static void hex_log(AVFormatContext *s, int level, const char *name, const uint8_t *value, int len)
97 if (av_log_get_level() < level)
99 ff_data_to_hex(buf, value, len, 1);
101 av_log(s, level, "%s: %s\n", name, buf);
104 static int kset(AVFormatContext *s, const uint8_t *r_val, const uint8_t *n_val, int len)
106 OMAContext *oc = s->priv_data;
108 if (!r_val && !n_val)
111 len = FFMIN(len, 16);
113 /* use first 64 bits in the third round again */
115 if (r_val != oc->r_val) {
116 memset(oc->r_val, 0, 24);
117 memcpy(oc->r_val, r_val, len);
119 memcpy(&oc->r_val[16], r_val, 8);
122 if (n_val != oc->n_val) {
123 memset(oc->n_val, 0, 24);
124 memcpy(oc->n_val, n_val, len);
126 memcpy(&oc->n_val[16], n_val, 8);
132 static int rprobe(AVFormatContext *s, uint8_t *enc_header, const uint8_t *r_val)
134 OMAContext *oc = s->priv_data;
138 if (!enc_header || !r_val)
142 av_des_init(&av_des, r_val, 192, 1);
143 av_des_crypt(&av_des, oc->m_val, &enc_header[48], 1, NULL, 1);
146 av_des_init(&av_des, oc->m_val, 64, 0);
147 av_des_crypt(&av_des, oc->s_val, NULL, 1, NULL, 0);
150 pos = OMA_ENC_HEADER_SIZE + oc->k_size + oc->e_size;
151 av_des_init(&av_des, oc->s_val, 64, 0);
152 av_des_mac(&av_des, oc->sm_val, &enc_header[pos], (oc->i_size >> 3));
156 return memcmp(&enc_header[pos], oc->sm_val, 8) ? -1 : 0;
159 static int nprobe(AVFormatContext *s, uint8_t *enc_header, const uint8_t *n_val)
161 OMAContext *oc = s->priv_data;
162 uint32_t pos, taglen, datalen;
165 if (!enc_header || !n_val)
168 pos = OMA_ENC_HEADER_SIZE + oc->k_size;
169 if (!memcmp(&enc_header[pos], "EKB ", 4))
172 if (AV_RB32(&enc_header[pos]) != oc->rid)
173 av_log(s, AV_LOG_DEBUG, "Mismatching RID\n");
175 taglen = AV_RB32(&enc_header[pos+32]);
176 datalen = AV_RB32(&enc_header[pos+36]) >> 4;
180 av_des_init(&av_des, n_val, 192, 1);
181 while (datalen-- > 0) {
182 av_des_crypt(&av_des, oc->r_val, &enc_header[pos], 2, NULL, 1);
183 kset(s, oc->r_val, NULL, 16);
184 if (!rprobe(s, enc_header, oc->r_val))
192 static int decrypt_init(AVFormatContext *s, ID3v2ExtraMeta *em, uint8_t *header)
194 OMAContext *oc = s->priv_data;
195 ID3v2ExtraMetaGEOB *geob = NULL;
199 av_log(s, AV_LOG_INFO, "File is encrypted\n");
201 /* find GEOB metadata */
203 if (!strcmp(em->tag, "GEOB") &&
205 !strcmp(geob->description, "OMG_LSI") ||
206 !strcmp(geob->description, "OMG_BKLSI")) {
212 av_log(s, AV_LOG_ERROR, "No encryption header found\n");
216 if (geob->datasize < 64) {
217 av_log(s, AV_LOG_ERROR, "Invalid GEOB data size: %u\n", geob->datasize);
223 if (AV_RB16(gdata) != 1)
224 av_log(s, AV_LOG_WARNING, "Unknown version in encryption header\n");
226 oc->k_size = AV_RB16(&gdata[2]);
227 oc->e_size = AV_RB16(&gdata[4]);
228 oc->i_size = AV_RB16(&gdata[6]);
229 oc->s_size = AV_RB16(&gdata[8]);
231 if (memcmp(&gdata[OMA_ENC_HEADER_SIZE], "KEYRING ", 12)) {
232 av_log(s, AV_LOG_ERROR, "Invalid encryption header\n");
235 oc->rid = AV_RB32(&gdata[OMA_ENC_HEADER_SIZE + 28]);
236 av_log(s, AV_LOG_DEBUG, "RID: %.8x\n", oc->rid);
238 memcpy(oc->iv, &header[0x58], 8);
239 hex_log(s, AV_LOG_DEBUG, "IV", oc->iv, 8);
241 hex_log(s, AV_LOG_DEBUG, "CBC-MAC", &gdata[OMA_ENC_HEADER_SIZE+oc->k_size+oc->e_size+oc->i_size], 8);
244 kset(s, s->key, s->key, s->keylen);
246 if (!memcmp(oc->r_val, (const uint8_t[8]){0}, 8) ||
247 rprobe(s, gdata, oc->r_val) < 0 &&
248 nprobe(s, gdata, oc->n_val) < 0) {
250 for (i = 0; i < sizeof(leaf_table); i += 2) {
252 AV_WL64(buf, leaf_table[i]);
253 AV_WL64(&buf[8], leaf_table[i+1]);
254 kset(s, buf, buf, 16);
255 if (!rprobe(s, gdata, oc->r_val) || !nprobe(s, gdata, oc->n_val))
258 if (i >= sizeof(leaf_table)) {
259 av_log(s, AV_LOG_ERROR, "Invalid key\n");
265 av_des_init(&oc->av_des, oc->m_val, 64, 0);
266 av_des_crypt(&oc->av_des, oc->e_val, &gdata[OMA_ENC_HEADER_SIZE + 40], 1, NULL, 0);
267 hex_log(s, AV_LOG_DEBUG, "EK", oc->e_val, 8);
270 av_des_init(&oc->av_des, oc->e_val, 64, 1);
275 static int oma_read_header(AVFormatContext *s,
276 AVFormatParameters *ap)
278 static const uint16_t srate_tab[6] = {320,441,480,882,960,0};
279 int ret, framesize, jsflag, samplerate;
280 uint32_t codec_params;
282 uint8_t buf[EA3_HEADER_SIZE];
285 ID3v2ExtraMeta *extra_meta = NULL;
286 OMAContext *oc = s->priv_data;
288 ff_id3v2_read_all(s, ID3v2_EA3_MAGIC, &extra_meta);
289 ret = avio_read(s->pb, buf, EA3_HEADER_SIZE);
290 if (ret < EA3_HEADER_SIZE)
293 if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}),3) || buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
294 av_log(s, AV_LOG_ERROR, "Couldn't find the EA3 header !\n");
298 oc->content_start = avio_tell(s->pb);
301 eid = AV_RB16(&buf[6]);
302 if (eid != -1 && eid != -128 && decrypt_init(s, extra_meta, buf) < 0) {
303 ff_id3v2_free_extra_meta(&extra_meta);
307 ff_id3v2_free_extra_meta(&extra_meta);
309 codec_params = AV_RB24(&buf[33]);
311 st = avformat_new_stream(s, NULL);
313 return AVERROR(ENOMEM);
316 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
317 st->codec->codec_tag = buf[32];
318 st->codec->codec_id = ff_codec_get_id(codec_oma_tags, st->codec->codec_tag);
321 case OMA_CODECID_ATRAC3:
322 samplerate = srate_tab[(codec_params >> 13) & 7]*100;
323 if (samplerate != 44100)
324 av_log_ask_for_sample(s, "Unsupported sample rate: %d\n",
327 framesize = (codec_params & 0x3FF) * 8;
328 jsflag = (codec_params >> 17) & 1; /* get stereo coding mode, 1 for joint-stereo */
329 st->codec->channels = 2;
330 st->codec->sample_rate = samplerate;
331 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
333 /* fake the atrac3 extradata (wav format, makes stream copy to wav work) */
334 st->codec->extradata_size = 14;
335 edata = av_mallocz(14 + FF_INPUT_BUFFER_PADDING_SIZE);
337 return AVERROR(ENOMEM);
339 st->codec->extradata = edata;
340 AV_WL16(&edata[0], 1); // always 1
341 AV_WL32(&edata[2], samplerate); // samples rate
342 AV_WL16(&edata[6], jsflag); // coding mode
343 AV_WL16(&edata[8], jsflag); // coding mode
344 AV_WL16(&edata[10], 1); // always 1
345 // AV_WL16(&edata[12], 0); // always 0
347 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
349 case OMA_CODECID_ATRAC3P:
350 st->codec->channels = (codec_params >> 10) & 7;
351 framesize = ((codec_params & 0x3FF) * 8) + 8;
352 st->codec->sample_rate = srate_tab[(codec_params >> 13) & 7]*100;
353 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
354 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
355 av_log(s, AV_LOG_ERROR, "Unsupported codec ATRAC3+!\n");
357 case OMA_CODECID_MP3:
358 st->need_parsing = AVSTREAM_PARSE_FULL;
362 av_log(s, AV_LOG_ERROR, "Unsupported codec %d!\n",buf[32]);
366 st->codec->block_align = framesize;
372 static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
374 OMAContext *oc = s->priv_data;
375 int packet_size = s->streams[0]->codec->block_align;
376 int ret = av_get_packet(s->pb, pkt, packet_size);
381 pkt->stream_index = 0;
384 /* previous unencrypted block saved in IV for the next packet (CBC mode) */
385 av_des_crypt(&oc->av_des, pkt->data, pkt->data, (packet_size >> 3), oc->iv, 1);
391 static int oma_read_probe(AVProbeData *p)
394 unsigned tag_len = 0;
397 /* version must be 3 and flags byte zero */
398 if (ff_id3v2_match(buf, ID3v2_EA3_MAGIC) && buf[3] == 3 && !buf[4])
399 tag_len = ff_id3v2_tag_len(buf);
401 // This check cannot overflow as tag_len has at most 28 bits
402 if (p->buf_size < tag_len + 5)
407 if (!memcmp(buf, "EA3", 3) && !buf[4] && buf[5] == EA3_HEADER_SIZE)
408 return AVPROBE_SCORE_MAX;
413 static int oma_read_seek(struct AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
415 OMAContext *oc = s->priv_data;
417 pcm_read_seek(s, stream_index, timestamp, flags);
420 /* readjust IV for CBC */
421 int64_t pos = avio_tell(s->pb);
422 if (pos < oc->content_start)
423 memset(oc->iv, 0, 8);
425 if (avio_seek(s->pb, -8, SEEK_CUR) < 0 || avio_read(s->pb, oc->iv, 8) < 8) {
426 memset(oc->iv, 0, 8);
435 AVInputFormat ff_oma_demuxer = {
437 .long_name = NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
438 .priv_data_size = sizeof(OMAContext),
439 .read_probe = oma_read_probe,
440 .read_header = oma_read_header,
441 .read_packet = oma_read_packet,
442 .read_seek = oma_read_seek,
443 .flags = AVFMT_GENERIC_INDEX,
444 .extensions = "oma,omg,aa3",
445 .codec_tag = (const AVCodecTag* const []){codec_oma_tags, 0},